Personal care products are those applied to the skin and/or hair, examples of which are moisturizers, cleansers, toners, barrier creams, shampoos, and styling and setting gels. Such products are usually formulated as creams (oil in water emulsions), or clear gels which may contain substantial quantities of water miscible alcohols or glycols. All use thickeners/stabilizers to modify rheological properties and to improve stability.
Conventionally both natural and synthetic materials have been used for this purpose. Natural products (e.g. gum arabic, guar gum or starches) vary in quality and hence performance. They also result in products of only a limited shelf life. Synthetic materials are more commonly used having a more consistent quality giving products of better stability. Currently used synthetics are all solids or powders of polymers having residual acid groups, which have to be dispersed or dissolved in water then neutralised before becoming effective. This is because the thickening capability of such compounds is pH dependent; they will not thicken until the acid groups have been neutralised. Great care is needed to prevent agglomeration and lump formation; hours of mixing may be needed before a stable dispersion is achieved.
A significant advantage for the personal care products and pharmaceuticals industry would be to provide a polymer composition which would serve both as a thickener and as a stabilizer and was also in liquid form to enable easy handling by automatic dispensers, metering pumps etc, and which is readily dispersible.